This invention relates to a method for operating an internal combustion engine having a crankcase in which there is rotatably supported a crankshaft to which there is articulated at least one connecting rod, which bears a piston that is moved in a cylinder covered by a cylinder head so as to form a working chamber, an air-gas mixture being supplied as main fuel to the working chamber via a charge changing duct in the cylinder head, the supplied air-gas mixture being at least momentarily enriched with an enriching fuel, an ignition device being present in the cylinder head and the enriching fuel being introduced into an ignition chamber of the ignition device. The invention further relates to an internal combustion engine so fashioned.
Such a method and such an internal combustion engine are known from DE 29 21 997 A1. This document discloses an ignition system for a gas engine in which an insert, made up of a cylindrical assembly that accepts an ignition device and an enriching fuel supply tube fashioned as a duct together with an ignition chamber positioned ahead of the cylindrical assembly on the combustion chamber side, is inserted into the cylinder head. Statements are further made as to stoichiometric air/fuel mixtures of the air-gas mixture and of the enriching fuel.
The further known EP 0 906 500 B1 discloses an ignition system for a gas engine in which an ignition chamber is inserted into the cylinder head, in which ignition chamber an air-gas mixture can be inflamed via an ignition device. The ignition chamber can be sealed off from the working chamber of the internal combustion engine. This design makes possible an exact and reliable determination of the time of inflammation of the air-gas mixture.